Sewing machine needle positioner



United States Patent 1 13,538,871

[72] Inventor Paul C. Trilli [56] References Cited 213 Alpha Ave., WindGap, Pennsylvania UMTED STATES PATENTS 18091 3,026,835 3/1962 Hall112/221 [21] Appl. No. 832,153 Filed June 11,1969 3,387,579 6/1968Ciccotelli 112/221 FOREIGN PATENTS [45] Patented N0v.l0, 1970 434,2694/1948 Italy 112/221 Primary Examiner-H. l-lampton l-lunterAttorney-John N. Randolph [54] SEWING MACHINE NEEDLE POSITIONERsclalmssnmwmg Flgs' ABSTRACT: An attachment for an otherwiseconventional [52] U.S.Cl 112/219, single needle sewing machine whichfunctions automatically 192/144 to effect stopping of the needle inaraised position when [51] Int. Cl l, D05b 69/22 operation of the machineis interrupted, to enable the opera- [50] Field of Search .1 12/219(F.O.D.). tor to thread the needle or to remove the material beingsewed 219, 218. 220,221.67,87.(F1uid without manually turning the handwheel. to thus save time Digest), (Section Digest): 192/144:l88/(lnquired) and labor,

Patented Nov. 10, 1910 3,538,871

SEWING MACHINE NEEDLE POSITIONER SUMMARY A primary object of the presentinvention is to provide a completely mechanical attachment of extremelysimple construction which may be readily applied to a conventionalsingle needle sewing machine to automatically cause the needle to stopadjacent an extremity of its reciprocating travel when operation of themachine is interrupted.

Another object of the invention is to provide such an attachment whichfunctions completely automatic, without any special action on the partof the operator.

Various other objects and advantages of the invention will hereinafterbecome more fully apparent from the following description of thedrawing, illustrating a presently preferred embodiment thereof, andwherein:

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a fragmentary sideelevational view of a conventional single needle sewing machine, showingthe needle positioner attachment applied thereto;

FIG. 2 is an enlarged fragmentary vertical sectional view, partly inside elevation, showing parts of the attachment and conventional partsof the sewing machine with which said attachment parts are associated,and

FIG. 3 is an enlarged horizontal sectional view, taken substantiallyalong a plane as indicated by the line 3-3 of FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring morespecifically to the drawing, the needle positioner attachment in itsentirety and comprising the invention is designated generally 5 and isshown applied to a conventional single needle sewing machine, portionsonly of which have been illustrated and will be described only to theextent necessary to set forth the application of the attachment thereto.

The sewing machine, designated generally 6, includes a necdle bar 7which is mounted for vertical reciprocating movement in a needle barbushing 8, and which supports a needle 9 at its lower end in aconventional manner. The conventional means to effect reciprocatingmovement of the needle bar 7 has not been illustrated.

The positioning attachment 5 includes a cylinder 10 having a restrictedtubular neck 11 at its lower end which engages over the exposed upperend of the bushing 8 and which is detachably secured thereto by asetscrew l2.

The upper end of the needle bar 7, which protrudes from the upper end ofthe bushing 8, extends into the cylinder 10 and said upper end isprovided with an internally threaded upwardly opening socket 13, whichconstitutes the only modification of the sewing machine 6. A piston,designated generally 14, is secured to the upper end of the needle bar 7and operates in the cylinder 10. Said piston includes two discs 15 and16 of diameters less than the internal diameter of the cylinder 10 and acup shaped washer 17 which is clamped between the discs 15 and 16 by aheaded screw 18 which extends centrally through the parts 15, 16 and 17,and which is threadedly received in the socket 13 for attaching thepiston 14 to the needle bar 7. The down turned annular peripheralportion 19 of the washer l7 slidably engages the wall of the cylinder10.

The cylinder 10 has a top wall 20 which is suitably secured theretoafter attachment of the piston 14 to the needle bar 7. The wall 20 hasan opening or port 21. A lower portion of the cylinder 10 is providedwith a vent port 50.

A bracket arm 22 is secured to and extends outwardly from an upperportion of the cylinder 10 and has an upturned outer end 23 providedwith an opening 24. A lever 25 has a pair of transversely spaced ears 26extending downwardly therefrom and which straddle a part of the bracket22, which is located adjacent the cylinder 10, and which are connectedthereto by a pivot element 27 for mounting the lever 25 above thebracket 22 and cylinder 10 and for rocking movement relative thereto. Adisclike valve element 28 is secured by fastening means 29 to the underside of the lever 25, remote from its pivot 27 and is positioned toengage and close the port 21. The lever 25 has an upturned end 30located on the opposite side of the pivot 27 from the valve 28 and whichis spaced from the upturned bracket end 23.

A flexible wire 31 extends through and is slidably disposed in aflexible tubing 32. One end of the tubing 32 is secured in the bracketopening 24 by setscrew 33. One end of the wire 31 extends from saidtubing end through an opening 34 in the upturned lever end 30. Acompression spring 35 is mounted on the wire 31 between the bracket end23 and the lever end 30 for normally urging the lever 25 to rockcounterclockwise about its pivot 27 for holding the valve 28 in aposition for closing and sealing the port 21. A head 36 is secured tothe terminal of said wire end and is disposed on the other side of thelever end 30 from the spring 35.

The wire 31 and tubing 32 have opposite downwardly extending lower endsand the wire 31 has a terminal portion which protrudes from said lowerend of the tubing 32 and which is secured in an opening 37 of a block 38by a setscrew 39, as seen in FIG. 3. Block 38 has a second opening 40through which extends the treadle rod 41 of the sewing machine. Asetscrew 42 secures the block 38 to the rod 41 for up and down movementtherewith. The lower end of the treadle rod 41 is pivotally connected toan eye 43 secured to one end of a treadle 44 which is pivotally mountedat 45 intermediate of its ends. The opposite end of the treadle rod 41is pivotally connected to a pivotally mounted lever 46 which closes aswitch 47 of the electric motor 48 of the sewing machine when thetreadle 44 is rocked in a direction to exert a downward pull on thetreadle rod 40.

Accordingly, when the switch 47 is closed to energize the motor 48 tocause operation of the sewing machine 6, the downward movement of thetreadle rod 40 will exert a downward pull on the end of the wire 31connected to the block 38 to cause the other end of the wire 31, as seenin FIG. 2, to move from left to right, so that the head 36 will bepulled against the lever end 30 for rocking the lever 35 clockwise aboutits pivot 27 to elevate the valve element 28 and open the port 21. Whilethe port 21 is open, the piston 14 can reciprocate freely in thecylinder 10 with the needle bar 7, since the cylinder 10 is vented belowthe piston 14 by the port 50.

When the treadle 44 is rocked in the opposite direction, orcounterclockwise about its pivot 45 for elevating the treadle rod 40 tomove the lever 46 to a position to permit the switch 47 to open anddeenergize the motor 48 for stopping operation of the sewing machine 6,the wire end 31 attached to the block 38 will be displaced upwardly withsaid block through the tubing 32 andso that the end of the wire 31, asseen in FIG. 2, will be displaced from right to left through the opening34 to move the head 36 away from the lever end 30 to allow thecompressed spring 35 to return the valve 28 to its closed position byrocking the lever 25 in a counterclockwise direction. However, shouldthe movement of the valve 28 to a closed position occur during upwardtravel of the piston 14 as the sewing machine coasts to a stop thepressure in the cylinder 10, above the piston 14, will rock the lever 25clockwise against the action of the spring 35 to unseat the valve 28 toallow escape of air from the upper part of the cylinder 10 until thepiston 14 reaches the upper extremity of its travel. When this occursthe spring 35 will promptly close the valve 28 to create a vacuum in thecylinder 10 above the piston 14 to check reciprocation of the piston,needle bar 7 and needle 9 and for thus stopping the needle in its raisedposi tion of FIG. 1, so that the needle can be threaded or the materialbeing worked upon removed from the sewing machine withoutmanuallyturning the wheel 49 to elevate the needle. If movement of the piston14, needle bar 7 and needle 9 ceases during downward travel of saidparts, the vacuum in the cylinder 10, above the piston 14, will returnthe parts to their raised position of FIGS. .1 and 2.

Various modifications and changes are contemplated and may be resortedto, without departing from the function or scope of the invention.

Iclaim:

l. in a sewing machine having a reciprocating needle bar, a bushing forsaid needle bar, a motor, a treadle and a treadle rod for operating saidmotor, a needle positioner comprising a cylinder attached to anddisposed above said needle bar bushing, a piston secured to the upperend of said needle bar and disposed for operation in said cylinder, saidcylinder having a vent port disposed beyond each extremity of travel ofthe piston, a valve for closing one of said vent ports, spring meansnormally urging said valve to a closed position, and valve aetuatingmeans connected to said valve and including a wire having one endconnected to said treadle rod of the sewing machine whereby when thetreadle rod is moved in one direction to effect engaging of the electricmotor of the sewing machine a pull is exerted on the wire for moving thevalve to an open position for venting said cylinder port to allow thepiston to reciprocate freely in said cylinder, and when the treadle rodis moved in the opposite direction for deenergizing the motor, saidspring means urges said valve to said closed position for sealing saidport as the piston commences to move away from said port therebycreating a vacuum in the cylinder end containing said sealed port toresist travel of the piston away from said cylinder end thus stoppingthe needle bar and needle adjacent one extremity of movement of saidparts.

2. A sewing machine needle positioner as in claim 1, said valvecontrolled port being disposed at the upper end of the cylinder forstopping movement of the piston adjacent the upper extremity of itstravel whereby the needle will automatically be stopped in a raisedposition when operation of the sewing machine is interrupted.

3. A sewing machine needle positioner as in claim ll, a bracket armsecured to and extending outwardly from an upper portion of the cylinderand having an upturned outer end provided with an opening through whicha portion of the wire slidably extends, said valve actuating meansincluding a lever pivotally mounted on the bracket arm and on which saidvalve is supported for swinging movement into and out of engagement withsaid port, said lever having an upturned end disposed between the leverpivot and the upturned end of said bracket arm and through which saidwire slidably extends, said lever pivot being disposed between the valveand the upturned lever end, said spring means comprising a compressionspring mounted on the wire between the upturned ends of the bracket armand lever for urging the lever in a direction for moving the valve to aclosed position, and a head connected to the wire and disposed on theother side of the upturned lever end for rocking the lever in theopposite direction for opening the valve when a pull is exerted on thewire by said movement ofthe treadle rod in a direction for closing themotor switch.

4. A sewing machine needle positioner as in claim 3, and a flexibletubing enclosing a substantial portion of said wire having one endsecured in said bracket arm opening and an opposite end extending toadjacent the end of said wire which is connected to the treadle rod,said wire slidably engaging in said tubing.

5. A sewing machine needle positioner as in claim 4, a connectingelement, means adapted to adjustably connect said connecting element tothe treadle rod and means securing the wire to the connecting elementbeyond the end of the tubing located remote from said bracket arm.

